I have an unrelated question for you, Chen: Why are true blue laser pointers (higher than 405 nm) so expensive compared to other colors (such as green, red, or violet)? And do you think the true blue laser pointers will become more affordable in the near future?  

Here is my reply :

    The degree of laser power dangerous classifications are CI:<0.4mw, CII:0.4-1.0mW, CIIIA:1-5mW,  CIIIB:5-500mW, CIV:>500mW
    Manufacturer must put on warning labels on CII , CIIIA, CIIIB, CIV. 

1. CI:<0.4mW ( Not dangerous laser )

    This grade's laser has no any creature damage when being pointed , this level should be extreme safe for human because if point to skin , do not have any feeling , even use eye to see too . So it is absolutely safe . They might use on CD player or other small equipments .

2. CII:0.4-1.0mW ( Low power laser )

    This grade of laser won't injure skin , would not cause fire , and because of low power , when it point to human eyes ,  eye has enough time to blink , or turn head away to avoid these strong light . These are called "within reaction time " , the laser seems would not hurt people eyes too , but human eye can not see it for a long time , or it might cause hurt on Retina . 

3. CIIIA:1-5mW  ( Medium power laser )

     This grade laser still won't injure skin but in some situation , it might hurt eyes or even cause a blind . For example if laser beam pass lens , the laser beam might concentrate , then it become dangerous . This grade's laser should be signal light to show it is working or not . Better to have  a key switch too .

4. CIIIB:5-500mW  ( High power laser )

     This grade laser can hurt human eyes in whatever situation , as it is power higher enough , eyes has not enough time to blink , and people's skin can be injured , even it can cause a fire . Moreover , if point the laser to wall , the reflective light is still strong , it hurt eyes without sense . 

     This kind of laser should have Key switch , safety appliance , signal light , cut-off switch to stop laser at any time , warning label . It is better to wear laser protector for eyes before turn it on . 

5. More than 500mW ( Extreme Industry laser )

     This grade laser should mainly use on industry field or military field . For example laser cutting machine , imagine that the 1000mW CO2 laser can drill holes on steel plate ! Only typical man can touch the button switch . 

     However , according my practice :

     10-30MW has no feeling when use finger to touch laser beam , 30-50MW has little feeling of heat , 100-200MW feels quite hot , 200-600mW i dare not touch already , 1000mW i dare not go to see the beam . 

     Thanks your reading and sorry for my poor English . 

Good quality one always start strong and all along strong laser beam , it won't goes weak unless the battery is out .

Poor quality maybe start strong but soon the laser beam goes weak , it can not recoverable by changing new battery . 

Thanks for reading . 

When got idea , i have to use different software to assemble it . It cost lots of time .

But we think that is worth . because those are very interesting advertisement . 

In order to save it and let us track what we did , i save it here for people review . 

For this 1st advertisement , i just want to talk about safety of playing laser pointer .   Don't play laser pointer careless !

Thanks for reading !

     Thanks the god , I don't know how to express my exciting of new site start working , let me show some history :

      Screambuy.com started to consider to make in 2005 , at that moment , we were not good at site building , but we had lots of interesting products to sell , we studied hard , then i remember in the beginning of 2006 , we made it . But it was just a simple site , which just showed products online , but it was enough for us to tell old customers what we had . Unfortunately , We still had to pay more times on excel orders which is for negotiation , confirmation , proceeding etc. 

      About the beginning of 2007 , we decided to change , so that customer can buy small quantity products on site directly , and we paid times on big orders . at that time , we didn't know any site building code yet , we tried to use simple software to build , So Screambuy.com's first shop was simple , slow , and complicated . we had lots of good ideas , but could not realized .  

      The 1st site was changed into 2nd site because we can not bear of too much troubles on 1st one . I remember it should be Jul. - Sep. of 2007 . Again we paid lots of time to revise , but at last , the new site does not work for a long time , because freight is a headache to handle . The 2nd one does not support oversea freight caculation . 

      We asked some website design guys , they lead us to change again , in mid of 2008 , the 3rd site start working , which was good enough for us to sell lots items on site , we achieved our object , customers were satisfied it too . For a long time , we supposed that was good enough , no need to change . The 3rd one worked for 1 - 2 years , when total products reach 2000 pcs , we found that it was hard to have a good management on big quantity products , things started to go stuck . We dare not to change the site easily because too much working and unknown what happen on new design site . 

      I thinkwe started to consider 4th design in mid of 2009 , at last a talent gave us an idea of how to change , but it is a brand new system and need hard coding . It was almost impossible for us to upgrade into it .  But we didn't give up , we start to learn website coding , design , server info from the first step . It should be 6 months so that we knew how to make . Then we make a local site ( work in my computer only ) , install different module to test stability , put into some products to have trial test , consider how it works when putting on server , put into lots of products to test stability again ....  Of course , thousands of bug comes , we have to debug one by one , or sometimes , even can not solve it , we have to find other ways to try .

       I remember we started to make mirror site on internet during mid of 2010 , which we supposed it was good revise enough for future development . Then , those thousands of products have to move one by one into this new site . I don't know how to explain what a hard working . 

       Until today , one day before China middle Autumn , although there are lots of products we don't upload yet , we decide to let 4th designed new site instead of old 3rd one ! 

       I believe this 4th site should be far more better than before one , and there are many great functions . I will tell you in later topics . 

       Hope that every one will like it , if found errors , please contact us .  Thanks for reading !

Vinsion

Owner of Screambuy.com